Conformational behavior of two C-disaccharides, containing D-glucopyranose moiety at the non-reducing end and L- or D-2-deoxy-arabino-hexopyranose moiety at the reducing end, has been studied using MM3 calculations and NMR experiments. The obtained results show that the conformational preference around the C-glycosidic bond is the same in both compounds and corresponds with the exo-anomeric effect. On the other hand, both compounds differ markedly in the conformational arrangement around the C-aglycone bond where the population of conformers is controlled by 1,3-diaxial-like interactions.
两个C-
双糖的构象行为已经通过MM3计算和NMR实验进行了研究,其中一个在非还原端含有
D-葡萄糖基团,而在还原端含有L-或D-2-脱氧-阿拉伯-己糖基团。得到的结果表明,两种化合物的C-糖苷键周围的构象偏好相同,与外消旋异构效应相对应。另一方面,两种化合物在C-非糖基键周围的构象排列上有明显的差异,构象的种群受到1,3-二轴向相似作用的控制。